Combined half-mask and hood type protective respiratory device

ABSTRACT

A protective respiratory device (1) in the form of a half-mask (2) is designed to cover the nose and the mouth of the wearer and is combined with a bag-shaped hood (3) designed to enclose the head of the wearer and provided with a visor (12) in front. Round the bag opening, the hood (3) is provided with an elastic sleeve designed to surround the neck of the wearer in a tight-fitting fashion. A first elastic band (9) arranged in the hood extends between the two sides of the half-mask and is intended to be applied round the back of the head or the nape of the neck of the wearer. A second elastic band (13) arranged in the hood and extending rearwards from a hood portion corresponding to the forehead of the wearer is connected to the first band (9) at the back. The second band (13) is adapted to be placed over the crown of the head of the wearer and has such a width that it will then largely surround the head of the wearer also laterally.

BACKGROUND OF THE INVENTION

The present invention relates to a protective respiratory device in theform of a half-mask designed to cover the nose and the mouth of thewearer and combined with a hood designed to enclose the head of thewearer and provided with a visor in front.

It is essential to the function of such protective respiratory devices,as well as devices without a hood, that the mask, whether a full-facemask or a half-mask, is applied in a tight-fitting fashion to the faceof the wearer. To this end, protective respiratory devices are usuallyequipped with elastic and length-adjustable bands, more specifically afirst band extending from the two sides of the mask round the nape ofthe neck of the wearer, a second band extending from the two sides ofthe mask round the back of the head, and, in the case of a full-facemask, a third band extending from an upper portion of the mask rearwardsover the crown of the head to be connected to at least one of the othertwo bands.

It is true that the elasticity and the adjustability in length of thebands make it possible to adapt a protective respiratory device to fiteach particular wearer. However, such adaptation is time-consuming andshould preferably be done well in time before use, i.e. not when anemergency arises, which may make people panic, yet necessitating quickapplication of the device. Especially, this goes for so-called escapehoods, which are intended to be used in the event of a gas emission or afire and which are a combination of a half-mask covering the nose andthe mouth of the wearer, and a hood enclosing the head of the wearer,since the bands for keeping the half-mask in place are often so arrangedunder the hood as to be difficult of access. Also, prior-art protectiverespiratory devices often require some readjustment of the length of thebands or their position round the head to be completely tight.

SUMMARY OF THE INVENTION

In view of the deficiencies of prior-art protective respiratory devices,an object of the present invention is to provide a protectiverespiratory device of the type mentioned by way of introduction, whichdoes not require any adjustment of the band length, neither before norafter application of the mask, and which further does not require anyreadjustment of the position of the bands round the head by virtue of aningenious arrangement of the bands.

This object is achieved by a protective respiratory device which ischaracterised by a first elastic band provided inside the hood andextending between the two sides of the half-mask to be applied round theback of the head or the nape of the neck of the wearer, and a secondelastic band which is provided inside the hood and fixed therein infront and at the back and which extends rearwards from a portion of thehood corresponding to the forehead of the wearer and is connected to thefirst band, the second band being made of a soft elastic ribbon materialand intended to be placed over the crown of the head of the wearer andhaving such a width as then to surround the head of the wearer to alarge extent also laterally, the hood being, round the bag opening,provided with an elastic sleeve designed to surround the neck of thewearer in a tight-fitting fashion.

Thanks to the combination of a first elastic band extending preferablyround the nape of the neck, and an exceptionally broad second elasticband extending straight back over the crown of the head, the protectiverespiratory device according to the invention is extremely easy to puton. Thus, after pressing the mask against the face, one merely has topull the junction of the two bands back over the head to position thebands. The length of the bands need not be adjusted, primarily becausethe large width of the second band makes it possible to choose a verysoft elastic ribbon material for this band and still achieve the forcesrequired for fixing the mask in place, both vertically and laterally.

BRIEF DESCRIPTION OF THE DRAWING

A preferred embodiment of the invention will be described in more detailbelow with reference to the accompanying drawing, which is a side viewof an escape hood, certain parts being broken away for greater clarity.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The accompanying drawing shows an escape hood 1 in accordance with thepresent invention and which is intended for use in emergency situations,e.g. in the case of fire or gas emissions. The hood comprises aprotective respiratory device in the form of a half-mask 2 designed tocover the nose and the mouth of the wearer, and a hood 3 designed to bepassed over the head.

The mask 2 is made of soft silicone rubber and is, in front, providedwith a filter holder 4 carrying a replaceable filter 5. This filter maybe a gas filter or a particle filter, or a combination of the two.Inwardly of the filter 5, the mask 2 has an inhalation valve (notshown), and on both sides, the mask has exhalation valves 6. All thevalves are common non-return valves with easily movable membranes ofsilicone rubber.

In the transitional area between the facial portion of the mask 2 andthe filter holder 4, the mask 2 has a circumferential recess in which aflat ring 7 is non-rotatably applied in a form-fitting manner. On bothsides of the mask 2, approximately on a level with the mouth of thewearer, the ring 7 has attachments 8 in which a first elastic band 9 isfixed by snap-on hooks 10. The band 9 is intended to extend between thetwo sides of the mask 2 round the nape of the neck to apply the mask 2in a tight-fitting fashion against the face of the wearer.

The hood 3, which is made of a flexible gastight material, is bag-shapedand has, round the "bag opening", an elastic sleeve 11 which is soelastic that the hood 3 can readily be passed over the head of thewearer. Once the hood 3 is in place, the sleeve is intended to surroundthe neck of the wearer in a tight-fitting fashion. In front and justopposite the eyes of the wearer, the hood 3 has another opening in whicha visor 12 is provided. The visor 12, which is sealed against the hood3, is made of rigid transparent plastic and is so large that the visualfield of the wearer is but insignificantly restricted.

Apart from the two openings mentioned above, the hood 3 has openingsthrough which the filter holder 4 and the exhalation valves 6 sealinglyextend. The filter holder 4 with the associated filter 5 and theexhalation valves 6 are thus the only parts of the half-mask 2 that arenot contained in the hood 3.

A second elastic band 13, provided inside the hood 3 and intended toextend from the forehead of the wearer, over the crown of the head, anddown to the nape of the neck, is fixed to the front of the hood by afirst seam 14 which approximately follows the hair line of the wearer.This band is fixed to the back of the hood by two substantiallyhorizontal seams 15, 16. The seams 15, 16 are provided each on one sideof the first band 9, thereby forming a channel 17, through which thefirst band 9 passes, between the second band 13 and the hood 3.

The second elastic band 13 is very broad. When the wearer puts on theprotective respiratory device 1, this band surrounds the head, not onlyin the longitudinal direction from the forehead down to the nape of theneck, but also laterally to such an extent that every tendency towardsunintentional displacement of the mask is obviated, vertically as wellas laterally. Owing to its considerable width, the second band 13 may,in addition, be made of a very soft and pliable elastic ribbon material.As a result, the protective respiratory device 1 fits just abouteveryone, regardless of head size, despite the fact that the second band13, like the first band 9, has no means for adjusting the band length.

I claim:
 1. A protective respiratory device comprising a half-mask (2) designed to cover the nose and the mouth of the wearer, combined with a bag-shaped hood (3) designed to enclose the head of the wearer and provided with a visor (12) in front, characterised by a first elastic band (9) provided inside the hood (3) and extending between two sides of the half-mask (2) to be applied around the back of the head or the nape of the neck of the wearer, and a second elastic band (13) which is provided inside the hood (3) and fixed therein in front and at the back and which extends rearwards from a portion of the hood (3) corresponding to the forehead of the wearer and is connected to the first band (9), the second band (13) being made of a soft elastic ribbon material and arranged to be placed over the crown of the head of the wearer and having such a width as then to surround the head of the wearer to a large extent also laterally, the hood (3) being, around an opening thereof, provided with an elastic sleeve (11) designed to surround the neck of the wearer in a tight-fitting fashion. 